handleSubmit(e){
        e.preventDefault();

        if (this.state.username == ""){
            return this.addError('Prašome įvesti vartotojo vardą');
        }
        if (this.state.password == ""){
            return this.addError('Prašome įvesti slaptažodį');
        }

        fetch(config.server + '/sistemosprieinamumas/prisijungti', {
            method: "POST",
            headers: {
                "Accept": "application/json",
                "Content-Type": "application/json"
            },
            body: JSON.stringify({
                "username": this.state.username,
                "password": this.state.password
            })
        })
        .then(response => {
            if (response.status == 400){
                return this.addError('Blogi prisijungimo duomenys');
            }

            if (response.status == 200){
                return response.json();
            }
        })
        .then(response => {

        })

    }